I'm developing a prototype for a local area paging system using a Raspberry Pi (<[login to view URL]> <-- link is to the manufacturer of the micro computer board I am using).
The base unit (a Raspberry Pi with touch screen connected) will communicate simple data exchanges with the pagers (also Raspberry Pi) using a Bluetooth 3.0 dongle (300m range).
Involves programming (probably C++ and Python, but you're free to suggest better alternatives) a small number of procedures that interact with and manage Bluetooth on Linux OS. In addition to managing Bluetooth connectivity between the master and several slaves in the piconet, the program will also have some interaction with the Raspberry Pi circuit board running the OS (i.e. controlling GPIO pins to turn on/off motor and LEDs when paged, etc).
I've outlined what I believe will be all the functions and what they will need to do, and I can provide this information upon getting started. In total, there are about 5-6 procedures with primary functionality to simply communicate state changes from the pagers, and about the same number of different procedures that will operate the base unit.
Please, inquire only if you are experienced developing applications that interact with Bluetooth.